Copper acetate has been observed to be more active than hydrocortisone in the carageen foot oedema model of inflammation. It has been suggested that administration of copper acetate results in the formation of copper chelates in vivo and it is the chelate that is responsible for the anti inflammatory activity.
Copper complexes have been shown by Sorenson (1976) to be anti-arthritic.
The number of pharmacological activities of copper complexes in the model of chronic diseases continues to increase at a rapid rate (Sorenson (1983)).
It has also been reported that copper complexes have anti-inflammatory, anti-ulcer, anti-convulsive, anti-cancer and anti-diabetic activities (Sorenson (1983)).
(Copper II).sub.2 (acetyl salicylate).sub.4, (copper II).sub.2 [1-(p-chloro benzoyl)-5-methoxy-2-methylindole-3-acetate].sub.4 (hereinafter referred to as copper indomethacin), copper II (salicylate).sub.2 have been found to be more effective as analgesics than their parent acids in the writhing mouse and adjuvant arthritic rat pain models. Copper indomethacin has also been found to be as effective as morphine in both laboratory models.
Prior to this invention, preparations of copper indomethacin have been only laboratory items of no apparent benefit to man or domestic animals. The inventors have shown a clinically useful and safe drug.
Copper indomethacin has been found to be more efficient than indomethacin on its own and is also more efficient than phenylbutazone.
Present medical treatment of shin soreness and other musculo-skeletal inflammation in horses involves mainly administration of nonsteroidal anti-inflammatory drugs (NSAIDs). For example, phenylbutazone has been the definitive drug used in the race horse industry for many years. However phenylbutazone has a long and unpredictable excretion and while the pharmacological actions of this drug may be complete within 24 hours, undesirable detection may continue in plasma and urine for long periods after cessation of treatment. This is of importance to animals required to compete drug-free. Furthermore, phenylbutazone has established and widely reported gut toxicity in the horse.
Indomethacin itself has a half-life of 2 to 11 hours which means it must be administered 2 to 3 times daily to be effective (Flower, R. J., Moncado, S., and Vane, J. R. (1985) Analgesic-Antipyretics and Anti-Inflammatory Agents: Drugs employed in the treatment of gout. In: "The Pharmacological Basis of Therapeutics" 7th Ed. Eds Gilman, A. G., Goodman, L. S., Rall, T. W., and Murad, F. MacMillan, New York, 1985).
While it is known that indomethacin has an anti-inflammatory action, it is also known that it causes gastrointestinal reaction in some mammals e.g. dogs and humans. These reactions include single or multiple ulcerations of the oesophagus, stomach and duodenum. Attempts to reduce these gastro-intestinal effects have been made by taking the oral drug immediately after meals, with food, milk or antacids, or antiulcer compounds.
Furthermore, NSAIDs have an analgesic effect which is partly a result of and independent of, and partly dissociated from, their anti-inflammatory action. This dissociation varies from drug to drug. Thus analgesia obtained from phenylbutazone and, to a lesser extent indomethacin is primarily a result of its anti-inflammatory action.